Positioning coupling for a table bracket

ABSTRACT

A machine having a cylindrical beam and a support capable of placing the beam horizontally, and rotatably adjustable in this position, is provided with a coupling interengaging a table bracket with the support to lock the bracket against rotation about the axis of the beam. The beam is itself rotatably adjustable with respect to the support about the beam axis. The coupling permits the bracket to be locked in a selected position while the beam is angularly adjusted about its own axis for various purposes.

United States Patent [1 1 Morse [4 Feb. 26, 1974 POSITIONING COUPLINGFOR A TABLE BRACKET [76] Inventor: Glenn B. Morse, 321 Fountain N.

13., Grand Rapids, Mich. 49503 [22] Filed: Aug. 28, 1972 [21] Appl. No.:284,417

[52] US. Cl 144/1 C, 83/477.1, 83/4772, 83/698, 144/35 R, 90/17, 287/14,408/20 [51] Int. Cl. B27c 9/02 [58] Field of Search.. 287/14; 83/477,477.1, 477.2, 83/478, 698; 144/1 R, 1 C, 1 G, 1 D, l H, l J, 35 R, 35 A;90/17; 408/234, 236, 20; 29/568 [56] References Cited UNITED STATESPATENTS 3,709,622 1/1973 Morse 144/1 C X 2,963,057 12/1960 Morse 144/] C2,623,269 12/1952 Goldschmidt 144/1 C 2,835,289 5/1958 Rockwell 144/1 CFOREIGN PATENTS OR APPLICATIONS 1,127,608 9/1968 Great Britain 287/14Primary ExaminerAndrew R. Juhasz Assistant Examiner-W. D. Bray [57]ABSTRACT A machine having a cylindrical beam and a support capable ofplacing the beam horizontally, and rotatably adjustable in thisposition, is provided with a coupling interengaging a table bracket withthe support to lock the bracket against rotation about the axis of thebeam. The beam is itself rotatably adjustable with respect to thesupport about the beam axis. The coupling permits the bracket to belocked in a selected position while the beam is angularly adjusted aboutits own axis for various purposes.

3 Claims, 7 Drawing Figures POSITIONING COUPLING FOR A TABLE BRACKETBACKGROUND OF THE INVENTION Experience has shown that a multiple purposemachine of the type shown in U. S. Pat. No. 2,963,057 can be used as abase for a practically endless series of attachments by supporting theattachments on the table of the machine and driving them with a beltsheave held in the chuck of the machines power head. Without theattachments, the machine is essentially a drill press, with a pivotedstand capable of placing the beam carrying the power head in variouspositions between vertical and horizontal. The table of the drill pressis mounted on the usual table bracket, which is slidable along this beamin the usual manner associated with the column of the floor model drillpress. When the base machine is placed in the horizontal position, andthe table surface is also placed in a horizontal position by appropriateadjustment, the power head (together with the column) can be rotatedabout its own axis while the table is held horizontal, thus providing anexcellent form of belt-tensioning accommodation, and also permitting themost convenient form of installation and removal of the belt that can beimagined.

The difficulty encountered with using a machine of a type shown in U. S.Pat. No 2,963,057 for this type of belt adjustment has centered in themaintenance of the position of the table so that the power head could berotated about the beam axis without correspondingly rotating the table.What is really desirable is a rotation of the power head with respect tothe table, while the table remains horizontal. The problem deals notonly with convenience, but with safety. An attachment of substantialweight placed on the table will cause a serious danger if all of theclamping system is relaxed to a degree necessary to affect an angularadjustment about the beam axis between the table and the power head.

SUMMARY OF THE INVENTION A machine of a type shown in U. S. Pat.2,963,057 is provided with a coupling preferably axially interengagingthe table bracket with the structure supporting the cylindrical columnbeam carrying the power head. This coupling is adapted to place thetable surface in horizontal position, so that the column beam can berotated with respect to the table, thus permitting the power head toswing downward without affecting the position of the table. When theclamping arrangements securing the adjusted position of the column tothe support structure, and the table bracket to the column, aretightened, the entire assembly becomes a secure structure. The clampingsystems can be relaxed to provide for further adjustment or fordisengagement and removal of the belt without generating a risk ofdropping the table and any attachments that happen to be mounted on it.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of themachinepositioned with the power head in the vertical position preparatory tofunctioning as an ordinary drill press.

FIG. 2 is a front view in perspective showing the machine illustrated inFIG. 1 with the power head in the horizontal position, and with thetable supporting a conventional band saw.

FIG. 3 is a perspective view on an enlarged scale of the belt driveassociating the band saw shown in FIG. 2 with the power head of themachine.

FIG. 4- is a perspective view similar to FIG. 3, showing a position ofthe power head spindle appropriate for installation or removal of thebelt, with the belt in a relaxed condition.

FIG. 5 is a perspective view showing the manner in which a drivingsheave is held in position for receiving a belt, and illustrating themanner in which rotation of the power head about the column beam axisproduces a movement of the driving sheave with respect to the table.

FIG. 6 is a view of the conventional belt system in the power head ofthe drill press, and the latch mechanism used for holding the hoodcovering this mechanism in the closed position.

FIG. 7 is a section on a vertical plane showing the hood latch on anenlarged scale.

DESCRIPTION OF THE PREFERRED EMBODIMENT The machine shown in FIG. 1 isequipped with a power head generally indicated at 10, which is the sameas that associated with an ordinary drill press. The motor 11 drives aspindle carrying the chuck 12 through a power transfer system concealedbeneath the hood 13. The handle 14 rotates the shaft 15 to advance thespindle in a downward direction, all of which is standard drill pressconstruction. The controls of the machine are normally in the form ofpush buttons as indicated at 16, which are electrically connectedthrough concealed wiring to control the motor 11.

The power head assembly 10 is clamped rigidly to the cylindrical columnbeam 17 by conventional arrangements (not shown). This beam is rotatablewithin the front pivot member 18, which is slotted over a part of itslength at 19 to provide a small degree of peripheral resilience so thatthe clamping bolt 20 can be tightened to constrict the member 18 aboutthe beam 17 and secure the beam angularly and axially with respect tothe support structure. The member 18 has a pivot shaft (not shown)extending through the the rear pivot member 21, and secured in positionby the nut 22. The latter can be tightened to determine the degree ofresistance to rotation of the front pivot member 18 with respect to therear pivot member 21. A set screw 23 is in threaded engagement with therear pivot member 21, and extends into engagement with the pivot shaftto lock the adjusted position of the front pivot member at a selectedposition between vertical and horizontal. The rear pivot member is fixedwith respect to the rear column 24, which is also fixed with respect tothe U- shaped based 25.

The table 26 is rotatably connected to the table bracket 27, which isslidable axially on the beam 17, and is also rotatable with respect tothe beam 17. The rotatable mounting of the table to the bracket isprovided by a suitable bolt to the table bracket with the bolt thusdetermining the axis of rotatable adjustment of a table with respect tothe bracket. The selected position of the table bracket with respect tothe beam is established by tightening the clamping bolt 28, whichconstricts the table bracket about the beam.

When the power head (and the column beam 17) are swung into thehorizontal position shown on FIG. 2, and the table 26 positioned asshown (with the table swung downward), the underside of the table (withrespect to the position shown in FIG. 1) becomes a solid shelf on whichattachments may be placed for receiving power from the power head withsuitable belt power-transfer systems.-FIG. 2 illustrates the placementof a conventional band saw 29 in such a position. The offset arm 30 ofthe table establishes two different heights for the table (accompaniedby a 180 rotation between these positions), and the lower table positionshown in FIG. 2 is particularly appropriate for attachments similar tothe band saw 29 which have substantial height. The selection between thetwo vertically-spaced positions of the table can be made on the basis ofplacing the working surface 31 of the band saw at the best level for theoperator.

A convenient arrangement for mounting the band saw 29 on the table 26involves the securing of the band saw directly to a plate 32 with boltsas shown at 33-35, together with a securing of the plate to the tablewith a bolt traversing the central table hole 36 shown best at FIG. 5.This hole is normally provided in a drill press table for drillingclearance. In addition to the bolt through the hole 36, the plate 32 hasa tongue 37 that slips easily between the flanges 38 and 39 of theoffset arm 30, so that the tongue can be used as a means of orientingthe position of the band saw as is placed on the table. With the tongueengagement, as shown in FIG. 3, the passage of a bolt through the plate32 and the table hole 36 will complete the securing of the band saw.

Power is supplied to the band saw sheave 40 through the belt 41 from thedriving sheave 42 mounted on the stub shaft 43 held in the chuck 12 of apower head. Due to the transverse relationship of the planes of rotationof the sheaves 40 and 42, a system of idler sheaves has to be used toestablish the proper course of the belt 41. A bracket 43 is adjustablysecured to the plate 32 by the bolts 44 and 45, which engage elongatedholes in the bracket 43 to permit an adjustment in the placement of thebracket 43 in the left-right direction, as viewed in FIG. 4. The idlersheaves 45 and 46 are respectively mounted on stub shafts 47 and 48secured by the nuts 49 and 50 to the bracket 43. The bracket 43 is bentto the illustrated configuration so as to place the idler sheaves 45 and46 appropriately to receive the various runs of the belt 41 as itengages the sheaves 40 and 42.

The installation of the belt 41 is accomplished most easily when thepower head is swung upward about the axis of the beam 17 to produce aslack condition of the belt, as shown in FIG. 4. This adjustment is madeby loosening the clamping bolt 20, which permits the rotation of thebeam 17 with respect to the front pivot member 18. It is verysignificant here that the standard feed adjustment of the drill presscontrolled by the handle 14 is used in the present arrangement as ameans of properly placing the plane of rotation of the sheave 42 toreceive the belt 41 as it leaves the idlers 45 and 46. This adjustmentis then locked by the quill clamp handle 51 associated with conventionaldrill press construction. The rotation of the entire power head withrespect to the front pivot member 18 produces a path of movement of thesheave 42 in the direction of the arcuate arrow shown in FIG. 5. Whenswung upward, the resulting position shown in FIG. 4 permits the belt 41to be slipped on or off with utmost ease. When the belt is in position,gentle downward pressure on the frontal area of the power head willswing the sheave 42 downward along its arcuate path to a pointcorresponding to the desired belt tension, at which the clamp bolt 20can be tightened to retain the adjustment. It should be noted in passingthat the installation of the belt 41 requires a 180 twist applied in acounterclockwise direction to the lower course of the belt as it leavesthe pulley 40, and before it is placed in engagement with the loweridler sheave 46. Twists of approximately 90 in the illustrateddirections are also applied to the courses of the belt 41 between thelower sheave 46 and the drive sheave 42, and between the drive sheave 42and the upper idler 45.

One of the factors that make the basic machine shown in FIG. 1 soattractive for the powering of a variety of attachments is theconventional power transmission normally concealed beneath the hood 13.In one conventional form of belt transmission, the motor 11 is arrangedto drive a central multiple-step idler 52 with the belt 53, with theidler driving the multiple-step sheave 54 with the belt 55. It iscustomary to provide a multiple-step sheave on the motor also, whichthus gives a double range of relative speed of rotation. A machine usinga standard motor adapted to run at approximately l,725 r.p.m. can beused to drive a wide range of equipment, which may require very lowspeed operation, as well as equipment requiring very high speed. Withoutfurther adaptation, a machine of the type illustrated in these drawingscan be used to operate a band saw at speeds appropriate for cuttingmetal, and also the much higher speeds appropriate for cutting wood,merely by by an adjustment of the belts 53 and 55.

In view of the horizontal position of the device, it is preferable touse a positive latch arrangement for securing the hood in position inorder to obtain its full benefits as a belt guard around high speed beltsystems. The hood latch is best shown in FIG. 7. The flanged plate 56 isconventional on drill press construction, and is closely surrounded bythe hood 13 when the hood is in the closed position shown in FIG. 1. Thehood latch is mounted on the bolt 57 traversing the peripheral flange ofthe plate 56, which is held between the head of the bolt 57 and the thinnut 58. A U-shaped clip 59 has its lower leg 60 bearing on the undersideof the plate 56, with opposite leg in the form of a tongue 61 engageablewith an appropriate hole 62 in the hood 13. A cone spring 63 biases theclip 59 to the right, as shown in FIG. 7, against the action of the nut64. The diameter of the base of the cone spring should be selected toexceed that of the nut 58. Loosening or tightening the nut 64 willengage or disengage the tongue 61 from the hole 62, and thus lock orrelease the hood. On release, the hood swings to the rear about aconventional hinge arrangement adjacent the motor 10.

It is obvious that the placement of an attachment of substantial size onthe table 26, as shown on FIG. 2, will result in a very strong tendencyto swing the table downward about the column beam 17. This, of course,can be counteracted by appropriate tightening of both the clamp bolts 20and 28. The manipulation of these in conjunction with the appropriatesetting of belt tension, while retaining the desired upright position ofthe band saw 29, is an extremly difficult maneuver. This problem iseliminated entirely by the arrangement shown in FIG. 5. The tablebracket 27 is provided with a fixed pin 65 located appropriately forengagement with the socket 66 in the end of the front pivot member 18.The axial sliding of the table bracket 27 toward the pivot member,accompanied by appropriate rotational placement, will produce acondition in which the pin 65 can interengage with the socket 66. Atthis point, it is obvious that the table bracket is restrained againstmovement about the axis of the beam 17, while the beam is still free torotate (with the power head) when the clamping bolt is released.lnterengagement of this coupling prior to placement of the band saw 29will result in removal of the problem and danger previously described. Acaution should be observed, however, against any attempt to move theentire beam assembly to the right, as shown in FIG. 2, with respect tothe front pivot member 18. This could be accomplished when the clampbolt 20 was loosened, whether or or not the bolt 28 was tightened. Anysuch movement would obviously disengage the coupling pin 65, and producea dangerous condition.

I claim:

I. A machine having a cylindrical beam and support means for said beamadapted to position said beam substantially horizontally, said beambeing adjustable about the axis thereof with respect to said supportmeans, said machine also having a power head, a table bracket slideableaxially on said beam and rotatable thereon, and a table mounted on saidbracket for angular adjustment about a mounting axis substantiallyperpendicular to the axis of said beam, said table having at least onesupporting surface substantially parallel to said mounting axis, whereinthe improvement comprises:

coupling means on said table bracket and support means, said couplingmeans being operative to lock said bracket against rotation with respectto said support means about the axis of said beam.

2. A machine as defined in claim 1, wherein said coupling means isinterengageable axially with respect to said beam.

3. A machine as defined in claim 2, wherein said coupling means is a pinon one of said bracket and said support means, and means forming asocket on the other of said bracket and said support means.

1. A machine having a cylindrical beam and support means for said beamadapted to position said beam substantially horizontally, said beambeing adjustable about the axis thereof with respect to said supportmeans, said machine also Having a power head, a table bracket slideableaxially on said beam and rotatable thereon, and a table mounted on saidbracket for angular adjustment about a mounting axis substantiallyperpendicular to the axis of said beam, said table having at least onesupporting surface substantially parallel to said mounting axis, whereinthe improvement comprises: coupling means on said table bracket andsupport means, said coupling means being operative to lock said bracketagainst rotation with respect to said support means about the axis ofsaid beam.
 2. A machine as defined in claim 1, wherein said couplingmeans is interengageable axially with respect to said beam.
 3. A machineas defined in claim 2, wherein said coupling means is a pin on one ofsaid bracket and said support means, and means forming a socket on theother of said bracket and said support means.